NIPPON PAINT PATENTS
CRATER INHIBITING METHOD
Patent No. U.S. 6,881,313 B2
Nippon Paint Co. has been granted
a patent for a method for inhibiting
a crater from occurring in a coated
film at the time when a coated
film is formed. The method comprises
cathodically conducting electrodeposition
coating on an object to be
coated and baking the electrodeposition
coated film. The electrodeposition
coating is conducted with a
cationic electrodeposition coating
composition which contains the following
aminopolyether modified
epoxy having polyether chain, as an
additive: the aminopolyether modified
epoxy having a number average
molecular weight of 20,000 to
100,000, obtained by allowing an
aminopolyether having polyalkylene
oxide chain and two primary amino
groups or secondary amino groups
and having a number average molecular
weight of 150 to 3000 to react
with a diepoxide having two epoxy
groups and having a number average
molecular weight of 300 to 7000 in
such amounts that the primary
amino groups or the secondary
amino groups of the aminopolyether
based on the epoxy groups of the
diepoxide is 1.05 to 1.8 in equivalent
ratio.